scholarly journals Gadd45g initiates embryonic stem cell differentiation and inhibits breast cell carcinogenesis

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Xinbao Zhang ◽  
Yuting Li ◽  
Junxiang Ji ◽  
Xin Wang ◽  
Meng Zhang ◽  
...  

AbstractMany self-renewal-promoting factors of embryonic stem cells (ESCs) have been implicated in carcinogenesis, while little known about the genes that direct ESCs exit from pluripotency and regulate tumor development. Here, we show that the transcripts of Gadd45 family genes, including Gadd45a, Gadd45b, and Gadd45g, are gradually increased upon mouse ESC differentiation. Upregulation of Gadd45 members decreases cell proliferation and induces endodermal and trophectodermal lineages. In contrast, knockdown of Gadd45 genes can delay mouse ESC differentiation. Mechanistic studies reveal that Gadd45g activates MAPK signaling by increasing expression levels of the positive modulators of this pathway, such as Csf1r, Igf2, and Fgfr3. Therefore, inhibition of MAPK signaling with a MEK specific inhibitor is capable of eliminating the differentiation phenotype caused by Gadd45g upregulation. Meanwhile, GADD45G functions as a suppressor in human breast cancers. Enforced expression of GADD45G significantly inhibits tumor formation and breast cancer metastasis in mice through limitation of the propagation and invasion of breast cancer cells. These results not only expand our understanding of the regulatory network of ESCs, but also help people better treatment of cancers by manipulating the prodifferentiation candidates.

Cancers ◽  
2021 ◽  
Vol 13 (5) ◽  
pp. 1005
Author(s):  
Lauren E. Hillers-Ziemer ◽  
Abbey E. Williams ◽  
Amanda Janquart ◽  
Caitlin Grogan ◽  
Victoria Thompson ◽  
...  

Obesity is correlated with increased incidence of breast cancer metastasis; however, the mechanisms underlying how obesity promotes metastasis are unclear. In a diet-induced obese mouse model, obesity enhanced lung metastasis in both the presence and absence of primary mammary tumors and increased recruitment of myeloid lineage cells into the lungs. In the absence of tumors, obese mice demonstrated increased numbers of myeloid lineage cells and elevated collagen fibers within the lung stroma, reminiscent of premetastatic niches formed by primary tumors. Lung stromal cells isolated from obese tumor-naïve mice showed increased proliferation, contractility, and expression of extracellular matrix, inflammatory markers and transforming growth factor beta-1 (TGFβ1). Conditioned media from lung stromal cells from obese mice promoted myeloid lineage cell migration in vitro in response to colony-stimulating factor 2 (CSF2) expression and enhanced invasion of tumor cells. Together, these results suggest that prior to tumor formation, obesity alters the lung microenvironment, creating niches conducive to metastatic growth.


2020 ◽  
Vol 48 (2-3) ◽  
pp. 116-118
Author(s):  
Damir Danolić ◽  
◽  
Luka Marcelić ◽  
Ilija Alvir ◽  
Ivica Mamić ◽  
...  

Metastases to the female genital tract from extra-genital primary cancers are uncommon and usually occur during widespread metastatic disease. Breast cancers are the most frequent primaries, predominantly the lobular type. Here, we report a case of a 55-year-old woman with breast cancer endometrial metastasis who presented with postmenopausal vaginal bleeding. We highlight the importance of endometrial sampling to confirm the diagnosis and distinguish primary from metastatic cancer of the endometrium since the treatment and prognosis of these conditions are entirely different.


Cancers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1909
Author(s):  
Tatiana S. Gerashchenko ◽  
Sofia Y. Zolotaryova ◽  
Artem M. Kiselev ◽  
Liubov A. Tashireva ◽  
Nikita M. Novikov ◽  
...  

Intratumor morphological heterogeneity reflects patterns of invasive growth and is an indicator of the metastatic potential of breast cancer. In this study, we used this heterogeneity to identify molecules associated with breast cancer invasion and metastasis. The gene expression microarray data were used to identify genes differentially expressed between solid, trabecular, and other morphological arrangements of tumor cells. Immunohistochemistry was applied to evaluate the association of the selected proteins with metastasis. RNA-sequencing was performed to analyze the molecular makeup of metastatic tumor cells. High frequency of metastases and decreased metastasis-free survival were detected in patients either with positive expression of KIF14 or Mieap or negative expression of EZR at the tips of the torpedo-like structures in breast cancers. KIF14- and Mieap-positive and EZR-negative cells were mainly detected in the torpedo-like structures of the same breast tumors; however, their transcriptomic features differed. KIF14-positive cells showed a significant upregulation of genes involved in ether lipid metabolism. Mieap-positive cells were enriched in genes involved in mitophagy. EZR-negative cells displayed upregulated genes associated with phagocytosis and the chemokine-mediated signaling pathway. In conclusion, the positive expression of KIF14 and Mieap and negative expression of EZR at the tips of the torpedo-like structures are associated with breast cancer metastasis.


2011 ◽  
Vol 8 (2) ◽  
pp. 222-238 ◽  
Author(s):  
Erik van den Akker ◽  
Bas Verbruggen ◽  
Bas Heijmans ◽  
Marian Beekman ◽  
Joost Kok ◽  
...  

Summary Multiple studies have illustrated that gene expression profiling of primary breast cancers throughout the final stages of tumor development can provide valuable markers for risk prediction of metastasis and disease sub typing. However, the identification of a biologically interpretable and universally shared set of markers proved to be difficult. Here, we propose a method for de novo grouping of genes by dissecting the proteinprotein interaction network into disjoint sub networks using pair wise gene expression correlation measures. We show that the obtained sub networks are functionally coherent and are consistently identified when applied on a compendium composed of six different breast cancer studies. Application of the proposed method using different integration approaches underlines the robustness of the identified sub network related to cell cycle and identifies putative new sub network markers for metastasis related to cell-cell adhesion, the proteasome complex and JUN-FOS signalling. Although gene selection with the proposed method does not directly improve upon previously reported cross study classification performances, it shows great promises for applications in data integration and result interpretation.


2020 ◽  
Author(s):  
C. Aban ◽  
A. Lombardi ◽  
G. Neiman ◽  
M.C. Biani ◽  
A. La Greca ◽  
...  

Epithelial to mesenchymal transition (EMT) is a critical cellular process that has been well characterized during embryonic development and cancer metastasis and it also is implicated in several physiological and pathological events including embryonic stem cell differentiation. During early stages of differentiation, human embryonic stem cells pass through EMT where deeper morphological, molecular and biochemical changes occur. Though initially considered as a decision between two states, EMT process is now regarded as a fluid transition where cells exist on a spectrum of intermediate states. In this work, using a CRISPR interference system in human embryonic stem cells, we describe a molecular characterization of the effects of downregulation of E-cadherin, one of the main initiation events of EMT, as a unique start signal. Our results suggest that the decrease and delocalization of E-cadherin causes an incomplete EMT where cells retain their undifferentiated state while expressing several characteristics of a mesenchymal-like pheno-type. Namely, we found that E-cadherin downregulation induces SNAI1 and SNAI2 upregulation, promotes MALAT1 and LINC-ROR downregulation, modulates the expression of tight junction occludin 1 and gap junction connexin 43, increases human embryonic stem cells migratory capacity and delocalize b-catenin. Altogether, we believe our results provide a useful tool to model the molecular events of an unstable intermediate state and further identify multiple layers of molecular changes that occur during partial EMT.


2020 ◽  
Author(s):  
Douglas W. Perkins ◽  
Syed Haider ◽  
David Robertson ◽  
Richard Buus ◽  
Lynda O’Leary ◽  
...  

SummaryDisseminated tumour cells, particularly in ER+ breast cancers, typically exhibit a period of dormancy that renders them insensitive to targeting by chemotherapy. Additionally, chemotherapy treatment can result in normal tissue damage, including the induction of cellular senescence. Using mouse and human breast cancer models, we demonstrate that systemic chemotherapy administration results in accumulation of long-lived senescent stromal fibroblasts and promotes metastatic outgrowth. Chemotherapy-induced senescent fibroblasts upregulate a senescence associated secretory phenotype (SASP) that accelerates 3D tumour spheroid growth by stimulating mitogenic signalling. Senolytic drugs can effectively eliminate chemotherapy-induced senescent fibroblasts in vitro, but show only modest efficacy in vivo, at least in part due to the upregulation of resistance mechanisms. In conclusion, systemic chemotherapy can establish a productive microenvironment for colonisation and outgrowth of disseminated cancer cells, however, optimisation of senotherapies for effective targeting of senescent fibroblasts is required to establish them as useful additions to standard chemotherapy.


2020 ◽  
Vol 4 (s1) ◽  
pp. 7-8
Author(s):  
Carlos Jesus Perez Kerkvliet ◽  
Amy R Dwyer ◽  
Caroline Diep ◽  
Robert Oakley ◽  
Christopher Liddle ◽  
...  

OBJECTIVES/GOALS: The glucocorticoid receptor (GR) is a ubiquitous steroid hormone receptor that is emerging as a mediator of breast cancer metastasis. We aim to better understand the biology associated with phospho-GR species in TNBC and their contribution to tumor progression. METHODS/STUDY POPULATION: To better understand how p-S134 GR may impact TNBC cell biology, we probed GR regulation by soluble factors that are rich within the tumor microenvironment (TME), such as TGFβ. TNBC cells harboring endogenous wild-type or S134A-GR species were created by CRISPR/Cas knock-in and subjected to in vitro assays of advanced cancer behavior. RNA-Seq was employed to identify pS134-GR target genes that are uniquely regulated by TGFβ in the absence of exogenously added GR ligands. Direct regulation of selected TGFβ-induced pS134-GR target genes was validated accordingly. Bioinformatics tools were used to probe publicly available TNBC patient data sets for expression of a pS134-GR 24-gene signature. RESULTS/ANTICIPATED RESULTS: In the absence of GR ligands, GR is transcriptionally activated via p38-MAPK-dependent phosphorylation of Ser134 upon exposure of TNBC cells to TME-derived agents (TGFβ, HGF). The ligand-independent pS134-GR transcriptome primarily encompasses gene sets associated with TNBC cell survival and migration/invasion. Accordingly, pS134-GR was essential for TGFβ-induced TNBC cell migration, anchorage-independent growth in soft-agar, and tumorsphere formation, an in vitro readout of breast cancer stemness properties. Finally, a 24-gene pSer134-GR-dependent signature induced by TGFβ1 predicts shortened survival in breast cancer. We expect to find similar results using an in-house tissue microarray. DISCUSSION/SIGNIFICANCE OF IMPACT: Phospho-S134-GR is a critical downstream mediator of p38 MAPK signaling and TNBC migration, survival, and stemness properties. Our studies define GR as a required effector of TGFβ1 signaling and nominate pS134-GR as a biomarker of elevated risk of breast cancer dissemination.


2021 ◽  
Author(s):  
Othman Benchama ◽  
Sergiy Tyukhtenko ◽  
Michael S. Malamas ◽  
Mark K. Williams ◽  
Alexandros Makriyannis ◽  
...  

Abstract While the prevalence of breast cancer metastasis in the brain is significantly higher in triple negative breast cancers (TNBCs), there is a lack of novel and/or improved therapies for these patients. Monoacylglycerol lipase (MAGL) is a hydrolase involved in lipid metabolism that catalyzes the degradation of 2-arachidonoylglycerol (2-AG) linked to generation of pro- and anti-inflammatory molecules. Here, we targeted MAGL in TNBCs, using the selective MAGL inhibitor AM9928 (hMAGL IC50 = 9nM, with prolonged pharmacodynamic effects of 46 hours residence time). AM9928 blocked TNBC cell adhesion and transmigration across human brain microvascular endothelial cells (HBMECs) in 3D co-cultures. In addition, AM9928 inhibited the secretion of IL-6, IL-8, and VEGF-A from TNBC cells. TNBC-derived exosomes activated HBMECs resulting in secretion of elevated levels of IL-8 and VEGF, which were inhibited by AM9928. Knockdown of MAGL by siRNA or treatment with AM9928 increased the expression of the adherent junction E-cadherin, known to be regulated by MAGL. Using in vivo studies of syngeneic GFP-4T1-BrM5 mammary tumor cells, AM9928 inhibited tumor growth in the mammary fat pads and attenuated blood brain barrier (BBB) permeability changes, resulting in reduced TNBC colonization in brain. Together, these results support the potential clinical application of MAGL inhibitors as novel treatments for TNBC.


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